if (!exceptions.isEmpty()) {
            fail("Concurrent operations caused exceptions: " + exceptions.get(0));
        }

        assertEquals(threadCount * opsPerThread, successCount.get(), "All operations should succeed");
    }

    /**
     * Test that session release with double-check pattern prevents race conditions.
     */
    @Test
    public void testSessionReleaseDoubleCheckPattern() throws Exception {

        // Prepare a minimal locator
        SmbResourceLocatorImpl loc = new SmbResourceLocatorImpl(ctx, smbUrl("smb://srv/share/path"));

        // Setup a tree that will fail with transport error first, then succeed
        SmbTreeImpl tree = mock(SmbTreeImpl.class);
        when(tree.acquire(false)).thenReturn(tree);

        CommonServerMessageBlockRequest req = mock(CommonServerMessageBlockRequest.class);

        // Second success should close the circuit (threshold is 2)
        result = circuitBreaker.executeWithCircuitBreaker(() -> "success 1");
        assertEquals("success 1", result, "Should execute second success");
        assertEquals(State.CLOSED, circuitBreaker.getState(), "Circuit should be CLOSED after success threshold");

        // Test max attempts in half-open with failure scenario
        circuitBreaker.trip(); // Open again

    }

    @Test
    void testTreeConnectAndDisconnect() throws Exception {
        SmbTree tree = new SmbTree(session, "testShare", "testService");

        // Mock transport.connect() to succeed
        doNothing().when(transport).connect();

        // Setup response for tree connect
        doAnswer(invocation -> {
            ServerMessageBlock request = invocation.getArgument(0);

        assertTrue(rateLimiter.checkAttempt("user1", "192.168.1.1"), "First attempt should be allowed");

        // Record success
        rateLimiter.recordSuccess("user1", "192.168.1.1");

        // Should still be allowed
        assertTrue(rateLimiter.checkAttempt("user1", "192.168.1.1"), "After success should be allowed");
    }

    @Test
    public void testAccountLockout() throws Exception {

                .thenReturn(sfd);

        // openCopyTargetFile should be called by serverSideCopy, so dest.openUnshared must succeed
        SmbFileHandleImpl dfd = mock(SmbFileHandleImpl.class);
        when(dest.openUnshared(anyInt(), anyInt(), anyInt(), anyInt(), anyInt())).thenReturn(dfd);

        // Refresh should clear the cache
        auth.refresh();
        Subject afterRefresh = auth.getSubject();
        // After refresh, may succeed or fail depending on JAAS configuration
        // Just verify that refresh doesn't break the authenticator
        assertNotNull(auth, "Authenticator should remain usable after refresh");
    }

    @Test

        URLStreamHandlerFactory mockFactory2 = mock(URLStreamHandlerFactory.class);

        Handler.setURLStreamHandlerFactory(mockFactory1); // First call, should succeed.

        assertThrows(IllegalStateException.class, () -> {
            Handler.setURLStreamHandlerFactory(mockFactory2); // Second call, should fail.

        PROTOCOL,
        /** Resource errors (out of memory, disk space, etc.) */
        RESOURCE,
        /** Configuration errors */
        CONFIGURATION,
        /** Transient errors that may succeed on retry */
        TRANSIENT,
        /** Unknown or unclassified errors */
        UNKNOWN
    }

    /**
     * Standard SMB error codes
     */
    public enum ErrorCode {
        // Network errors

                            response.writeBytesWireFormat(buffer, 0);
                        }
                        success[index] = true;
                    } catch (Exception e) {
                        success[index] = false;
                    }
                });
            }

            // When
            for (Thread thread : threads) {